METHOD FOR DEVELOPMENT OF DENSE OIL DEPOSIT BY ELECTRIC FRACTURE Russian patent published in 2020 - IPC E21B43/26 E21B43/17 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil industry and can be used in development of multilayer low-permeability oil formations with application of formation fracturing. Method includes drilling and / or selection of vertical, horizontal and / or directional wells already existing on the deposit. Providing use of electroconductive casing string and / or electroconductive cement ring. Electrodes are lowered into the well, and formation electric fracturing is performed due to creation of electric arc between electrodes. At that, reservoir is selected, in which water-bearing stratum is located below productive oil-bearing dense formation, at that oil-bearing and water-bearing strata coincide in structural plan. Distance between bottom of upper oil-bearing formation and roof of lower water-bearing formation shall not exceed 100 m. Formation electric fracturing is supplemented with hydraulic fracturing. After hydraulic fracturing of oil-bearing stratum and withdrawal of product from it to reduction of formation pressure to level, at which further operation of wells is not viable, electrodes of different polarity are placed in adjacent wells. Electrodes with one polarity are placed opposite the upper oil-bearing bed. Electrodes with opposite polarity are placed opposite the lower water-bearing stratum. After electric fracturing of the formation, these wells are left to redistribute pressure for 10–30 days for penetration of water into oil-bearing productive formation on previously created hydraulic fractures and in subsequent - electric fracture cracks until pressure increase in oil-bearing productive stratum. After that wells are let into production along upper oil-bearing formation. Conducting electric fracturing of the formation and waiting periods are repeated.

EFFECT: increasing oil recovery of a deposit.

1 cl, 3 ex